Text not showing

I’ve set up the Contact Us Form plugin, but when I try to type responses into the fields my responses are white and therefore invisible. (I can see that they’re there, though, because when I highlight them they appear.) Responses in the Capcha box are also invisible. How can I fix this? I’m unfortunately unversed in HTML and CSS, so simple instructions are greatly appreciated.

Here is my website: https://katiesonger.com/send-katie-an-email/

P.S. Apologies for the double post on my previous question on this forum. I’m still getting used to the WordPress forums and it was too easy to hit “Post” twice! ??

https://www.ads-software.com/plugins/contact-us-form/